Grades

UPDATE: a few Q7 scores were missing, I did not realize that the TAs still had a few of those. They are up to date now.

I have posted exam 3 grades and updated quiz grades. You can consider the exam, quiz average and homework averages listed to be finalized, excepting for any errors I might find in the spreadsheet or papers which I might have missed. This means that, yes, I have included one dropped quiz overall and two dropped homework problems per week. (And, no, I have not scaled exam 3 at all, the average was 79% so no scaling was necessary.)

I will be getting lab 4 grades from the TAs this afternoon, and will be able to post final grades tonight or tomorrow morning. If you seem to be missing any scores (excepting lab 4, which I have not posted yet), you have until Monday to let me know ... that's when I have to submit grades to UA. After that, it is hard to change things.

Grades are updated

through HW11 (so, final HW grades and average HW). Q7 isn't there, nor is the 4th lab/extra credit. Check to see that your grades show up correctly otherwise.

And, if you're reading this before dawn, get some sleep! It will help you more than any last-minute cramming will.

Quiz 7 and its solution

can now be found here. Recall that quiz 5 was the diagnostic test (which I can't post), and quiz 6 was the exam bonus (which isn't relevant for tomorrow's exam). Hence the gap in the quiz listing at the preceding link.

Updated solution to HW11

there was a small typo in the second to last equation. The θ² should just be θ. Carry on.

HW11 solutions

are here.

HW10 solutions

are here.

HW9 solutions

are here.

Grades updated

Includes updates to exam scores to reflect quiz 6. Includes HW through #9, including all dropped problems. 

Tomorrow's lab

simple harmonic motion.

Exam 3 practice questions

here. There may be more to come, but I'm not going to make any promises. 

Slides on waves

here you go.

Sections for exam 3

11.2-11
14.2-9
15.2-7
16.2-6
18.2-12

The exam format will be exactly like the last two. 

HW11 is out, due Friday

fluids and oscillations. The oscillations stuff should make sense after Thursday's lecture ...

Homework this week

There is no new homework due tomorrow. Instead, I will put out a homework set some time tonight that will be due on Friday. It will be a bit longer and cover fluids, waves, and vibrations.

Tomorrow's lab

will involve measuring buoyant forces. We'll start at 10am.

There will also be an extra-special quiz tomorrow that you really, really will not want to miss. I don't want to spoil the surprise, but let's just say it will help make up for your last exam score if you weren't totally happy with it.

Tomorrow's lab

you will verify Boyle's law (pressure times volume is constant at constant temperature for a fluid). It is short and very simple, so we will supplement it for some to-be-posted-later activities.

Exam 2 distribution

Average 76.4, standard deviation 12.2.

HW10 is out

a few short problems on gravitation and fluids.

No homework today

Just to confirm: there is no new homework today. Tomorrow there will be a short homework set on gravitation (today's lecture) and fluids (tomorrow's lecture), due Wednesday. 

Exam start time

You can start the exam as early as 09:00 tomorrow, but feel free to show up at 10:00 and you will probably have enough time (but the exam ends at 11:50 independent of your start time).

Don't, however, show up at 8:30 or something. No one will be there. Grab some coffee in Lloyd if you're around that early, you can cram there on the couches in comfort, rather than lining the hallway. 

Exam 2 formula sheet

example here. What you will receive with the exam tomorrow will be essentially the same, modulo any typos and omissions I uncover this evening.

Homework 8 solutions

are here. Given that I just did HW9.1-2 in class on Friday, and HW9.3 is not covered on the exam, HW9 solutions are not likely to appear until late tonight.

Practice problem solutions

are now finished. Note that rolling motion (last problem) is not covered.

To head off a likely question: yes, I will post the formula sheet you will get with the exam some time today. It is likely to be quite late before I finish it though.

Textbook sections for exam 2

7.3-8 (Work-KE)
8.2-8 (PE, conservation of energy)
9.4-10 (momentum)
10.2-10 (rotation, torque)

Exam 2 practice problems

Here's what I could get together quickly. There will be more (and the rest of the solutions) tomorrow or late tonight, but I have a thing this evening ... will be off the grid until about 10pm.

HW solutions and grades

I have homework solutions ready through HW7. HW8 may appear yet tonight, and I should also have the quiz solutions up as well. [Update: errors in HW7.1 solution now fixed.]

You will get your second lab reports back tomorrow, as well as HW7 and Q4 at least. Possibly HW8 as well. I should have those grades on eLearning before morning.*

Friday, we'll discuss angular momentum and torque, which may or may not take the whole period. Time permitting, we'll do a little bit of equilibrium and elasticity, or we may leave that until Monday.

*Except perhaps for those of you that submitted the second lab report by email. I got the graded hard copies back from the TAs today, but not the electronic ones yet. 

HW 9 is out

and here it is. Due Friday.

Thursday's lab

in which you will verify that work is the change in kinetic energy. Hopefully.

This one is a bit fussier than the others - if you are not careful taking your data, the results can be rather noisy, and you won't get good agreement. Focus on getting a couple of good curves to analyze carefully, even if it means repeating the measurements a few times until it looks decent, rather than jumping into the analysis.

Anyway: it does work, just fair warning.

No homework for Thursday

You've already have 8 homework sets in the books, so we can afford a break for one day ...

Elearning grades

should be current through HW6. The "HW Avg" column accounts for your 2 dropped problems per week.

If you seem to be missing HW or quiz scores, let me know right away. I have a few without names that have yet to be identified ...

Wednesday's lab

You will make things collide, and quantify the results.

Homework 8

find it here.

HW7 is out

and here it is.

Tomorrow's lab

can be found here.

Also, this.

Tomorrow's lab

I have not yet finalized the procedure for tomorrow's lab, but I will post it here once it is ready. Don't worry about reading this one ahead of time, you will have time enough in lab tomorrow to read through it.

We'll start at 10am tomorrow.

NO homework due Monday

In case you've been waiting for it, I decided not to assign anything new.

Grades on eLearning

I now have Q1-3 and HW1-3 on eLearning, as well as your HW average (accounting for the two dropped problems). Note that Q3 was mistakenly labeled "Quiz 4", I didn't catch that before the TAs printed them. Please make sure everything looks OK to be sure I didn't miss anything.

The exam scores are also there. As I mentioned in class, I took the best 4 questions out of 6 instead of the best 5 to scale it a bit. This gave an average of 74.7 and a standard deviation of 15, which is not so bad.   Here's a plot:

Over the weekend I should have at least HW4-5 scores posted, and hopefully HW6 too. Expect lab reports Monday morning.

HW6 is out

and can be found here. Just three problems on work and energy, due Friday.

HW4 solutions

are also ready.

UPDATE: the numbers I had for T₁; and T₂ in problem 2 were wrong. The formulas were correct, but apparently I was a bit sloppy with the calculator. Should be correct now ...

Quiz 2 solutions

are ready.

Quiz 3 solution

is ready. Quiz 2 and HW4 solutions will follow after I have some dinner ...

Exam 1 practice problems

Here is a small collection of problems and solutions, in case you want more practice. The "ph125" problems are harder than what I will ask, the "ph105" problems are about right.

Tutoring

If you find yourself a bit lost and need more help, you can always come by my office hours, or ask for another time we might meet. We also have one undergrad physics major who has offered to tutor people over the summer, David Thompson. You can contact him via davidt0504 on facebook, or I can provide his email address if you'd rather do it that way. Just mention that you're in my PH105 class and were looking for some tutoring. His rates are very reasonable, and he knows the PH105 stuff well.

Lab 4

can be found here. We'll do this lab tomorrow, please read it before the lab session. We will start at 10am again.

Exam 1

Exam 1 will happen this Thursday at 10am in the laboratory room (Gallalee 203). An example of the formula sheet I will give you with the test can be found here.

Not all of the sections that we will have covered by Thursday will be on the test. Specifically, the following sections will be on the test (referring to the 9th edition):

• Ch.2, Sect. 2-9
• Ch. 4, Sect. 2-6
• Ch. 5, Sect. 2-9
• Ch. 6, Sect. 2-3

The test will be 6 problems, and you must solve any 5 of them - so you can skip the one you think is hardest. Each problem will have multiple parts, so there is plenty of chance for partial credit (even within an individual part). To head off an obvious question: if you do all six, I may grade all six and take the best 5 as your grade. Or, I might just grade the first 5 I see. Who knows. Your best bet if you do all 6 is to tell me which 5 of them you want me to grade. Grading the exam will cost me 6-8 hours most likely,  so making it easier on me in any way you can is a good idea.


I will provide a formula sheet like the one linked above with all relevant constants and basic formulas,  sufficient to solve all of the problems. Additionally, you are allowed to bring in a single 8.5x11 inch sheet of paper with your own notes, formulas, etc. -- anything you want, really. Front and back sides are allowed. You are additionally allowed writing implements and a calculator (a calculator, not a cell phone or any network-enabled device). You can feel free to program your calculator in arbitrary ways, but no internet or peer-to-peer communication of any kind.

I don't know if I can stress enough that you should not forget your calculator.

HW5 is out

and you can find it here. Due at Wednesday's lecture. There will not be a homework due Thursday, owing to the exam.

Grades online

You can now view your grades online through eLearning ... I have grades for HW1-3 and Q1 posted right now.

I had plans to use another system which is less ... antiquated, but silly server issues got in my way. I won't use eLearning for anything but grades.

HW3 solutions are out

and here they are. Let me know if you see any mistakes. 

HW2 solution

find it here. Again a scan of my own handwritten solutions ... more than likely the HW3 solution, coming tonight, will be properly typed up. 

HW4 #3

For question 3 I'm expecting a purely symbolic answer - the fact that you're given a number for the force isn't of much help without knowing the masses, and that was part of the point I guess.

So: your answer should be in terms of the given force and variables representing the masses, m₁ and m₂. You are right in thinking you can't get an actual number for the acceleration without knowing values of the masses.

HW4 is out

here you go.

Quiz 1 and its solution

now available.

Notes from Friday's lecture

Find them here. As I mentioned in class, this stuff is "not on the test," but we will need these results later in the course. 

Monday's lab

Here is the procedure for Monday's lab.

A few of things to note.

(1) We'll start at 10am again, this should not be a lengthy lab.

(2) The lab is on force, which we haven't gotten to in lecture yet. However, most of it is really to do with acceleration, which we have covered, and what you need to know about force is fairly minimal. If you have done the reading for Monday (beginning of Ch. 5), it will make sense.

(3) The lab procedure doesn't talk about uncertainty analysis much. That isn't because you shouldn't do it. Quite the opposite, what you've learned so far should be part of your default analysis for labs from now on. Later in the week we'll learn a few more techniques for uncertainty analysis.

(4) Don't forget your lab reports are due ... it is fine if you want to print them when you get to the lab, electronic copies are also fine.

Next HW will not be due until Tues

Since we are just about to start a new topic, and I already asked some tougher questions about projectiles, there will not be a HW set due on Monday. The next HW will come out tomorrow and be due Tuesday afternoon.

HW1 solution

here you go. I normally wouldn't just post the handwritten version ... but I ran out of time to typset them nicely, and didn't want to make you wait any longer given the pace we have to keep. Hopefully they are readable enough. Feel free to ask questions if you still aren't sure how to work these problems out. The quiz and HW2 solutions should follow on Friday at some point.

[Looking at the solutions I just posted, I wish I had re-written the them to be a bit neater. What you're seeing is my first pass at solving the problems, FWIW.]